Apparatus for casting cylindrical bodies



(No Model.)

4 Sheets-Sheet 1. W. 0. FARNUM. APPARATUS FOR CASTING GYLINDRIGALBODIES. No. 482,405.

Patented Sept. 13, 1892.

H! M W Hlli WITNESSES NYENT UR:

(No Model.) 4 Sheets-Sheet 2.

W. G. FARNUM. APPARATUS FOR CASTING GYLINDRIGAL BODIES. No. 482,405.Patented Sept. 13, 1892.

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WITNESSES; INYEN'I'EIR:

m: warns FETERS co-. mum-mac vmsumzm'w u c (No Model.) 4 Sheets-Sheet 3.W. C. PARNUM. APPARATUS FOR CASTING GYLINDRIGAL BODIES. No. 482,405.Patented Sept. '13, 1892.

INYIBN'IEIR:

WM. [3. FARNUM, g c/hm/zh 6M 4 Sheets-Sheet 4.

(No Model.)

w. a, FARNUM. APPARATUS FOR CASTING GYLINDRIGAL BODIES- No. 482,405.Patented Sept. 18, 1892.

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INYEN'IEIR W ITNESEEE 'VV'M- E: F.ARNUM. /2 QZZWMM STATES PATENT OFFICE.

WILLIAM C. FARNUM, OF CHICAGO, ILLINOIS.

APPARATUS FOR CASTING CYLINDRICAL BODIES.

SPECIFICATION forming part of Letters Patent No. 482,405, datedSeptember 13, 1892.

Application filed February 9, 1888. Serial No. 263,438- (N m del-l Toall whom it may concern.-

Be it known that 1, WILLIAM C. FARNUM, of the city of Chicago, in thecounty of Cook and State of Illinois, have invented certain Improvementsin Apparatus for Casting Oylindrical Bodies, of which the followingdescription, in connection with the accompanying two sheets of drawings,constitutes a specification.

This invention relates to improvements in the art of making castings inrotating molds, wherein the molten metal is distributed to theperipheral parts of the mold when in rotation by centrifugal force, andalso to special construction of the apparatus, whereby the process ofmaking such castings is carried out.

The art of making castings in rotating molds under centrifugal force isnot new; but in the various processes and apparatus heretofore devisedfor use in making cylindrical castings, wherein rotation and centrifugalforce have been employed to equalize and condense the molten metal inits distribution to the periphery of the molds, failure has resultedfrom various causes. One difficulty has consisted in the fact that eachmold has generally been built so as to require its own independentdriving apparatus, from which it could not readily be detached, and suchapparatus duplicated for each mold was necessarily very expensive.Another difficulty to contend against is the fact that in using steel itis essential when the charge is in the right condition to pour off thewhole charge must be poured off at once, and if a large number ofcastings of moderate Weight are to be made an extensive duplication ofcostly machinery to rotate the several molds is essential to dispose ofa heavy charge of metal, and heavy charges are most desirable becausemost economical.

In some of the existing machines the construction of the molds and theirattachment to or connection with the driving apparatus has been suchthat great difficulties existed in removing the mold from the machineand in detaching the casting from the mold after or before such removal.These defects and objections have prevented the introduction of thismethod of making cylindrical castings, and it is to overcome theseobjections and eliminate such defects of construction that the presentapparatus has been devised.

The main advantages secured by this invention are simplicity andcheapness of the apparatus employed. The flasks containing the molds arethemselves cylindrical and are mounted upon and driven byfriction-rollers by rolling contact alone, and the flask, having no fastconnection with any part of the driving apparatus, can be rolled out ofposition in the machine in a moment at any time by stopping the machine.A number of sets of driving rollers can be arranged on asingle pair ofdriving-shafts, and thus a large number of molds can be rotated at onceand with a small outlay of driving-power. In pouring the metal thedirection and force of the cur rent are in the same direction as therotation of the molds, and as a result the metalis laid, as it were, inthe mold evenly and uniformly about its periphery with the leastpossible agitation and by a continuous stream. This, coupled with thecentrifugal force, tends to solidify the metal throughout the wholemold, and thereby eXpels gases and entirely obviates blow-holes. It alsofacilitates uniform shrinkage by producing in the pouring a uniformtemperature. Another result attributable to the influence of thecentrifugal force upon the metal as it is received in the mold is thatit will not flow in the mold, being confined to the point of impact asit enters the mold by such force. This result is secured by adjustingthe velocity of the current of metal as it leaves the mouth of therunner to correspond with the velocity of rotation of the mold at thepoint of impact. Compound castings made of two or more varieties ofmetal may be made by successively pouring the several kinds of metal inthe same mold, and under the influence of the centrifugal force exertedthereon the resultant product will be a casting made up of concentricrings of different metals, each ring or layer being united to its nextcontiguous layer by concentric fusion.

The construction and operation of my apparatus may be deduced from theaccompanying drawings, wherein- Figure 1 shows a side elevation of agang of fiasksand molds, one of the flasks and molds being shown indiametrical section. Fig. 2

shows an end elevation of the same. Fig. 3 shows a semicircular sideview of one-half of an annular mold. Fig. 4 shows a transverse section,on an enlarged scale, taken across one side of the annular mold. Fig.5is a sectional view of the column nut and screw whereby the height ofthe runners is adjusted. Fig. 6 shows a modification of the flask and ofthe means for centering and confining the mold therein. Fig. 7 showsanother modification of the flask and of provisions for preventing theflask from leaving the driving-rolls when in motion. Fig. 8 is a sideelevation of the apparatus shown in Fig. 7, and also exhibits a systemof driving and supporting rollers different from those shown in Fig. 2.Fig. 9 is a side and end elevation of one of the chucking-blocks usedbetween the inside of the flask and the edge of the mold, as seen inFig. 8. Fig. 10 is a side view of one of the links employed instructures like Figs. 6 and 7. Fig. ll shows a mold provided with adriving-rim cast integrally therewith. Figs. 12 and 13 exhibit partialviews of opposite sides of the same mold.

In this case the mold and flask are virtually consolidated. Fig. 14:shows another syle of yielding and centering device to be placed betweenthe edge of the mold and the interior of the flask.

In the several modifications or varieties of flasks shown in Figs. 1, 6,7, and 11 no specific construction of either is preferred to theexclusion of the others.

My invention may be divided into two branches for purposes ofelucidation and description, the first of which relates to the mold andflask and provisions for centering and holding the former within thelatter. The second relates to the mechanism for supporting, guiding, androtating the flask in use. The apparatus shown is designed for castingtires for car and locomotive wheels, but by a substitution of molds andflasks may be employed for making a great variety of annular orcylindrical castings.

In this specification I shall confine myself to such a style ofapparatus embodying my invention as is adapted to' making steel tiresfor car-wheels. The mold in which I cast the tire is seen in transversesection and half-plan in Figs. 1 and 3. It consists of two annularsections F and E, which meet at the joint 00x,

which is at the periphery of the flange of the wheel. This mold has onlysufficient depth radially to receive and retain sufficient amountofmaterial to cast a tire and afford enough internal surplus to providefor turning and truing up the inside of the tire to fit the rim of thecar-Wheel. Each section of the mold has cast on its exterior raisedradial ribs or ledges h h, which when the mold is chucked in the flaskbear against the wall of the flask on one side and against thecover-plate on the other. The intervals K K between ribs h it constitutean air space, through which a circulation of air passes when the flaskis rapidly revolved.

Such circulation, generated by centrifugal force exerted on the airbetween the edge of the mold and the walls of the flask, contributes tothe cooling of the mold and flask after the mold is charged. The ribs hh may as well be on the interior of the flask as on the exterior of themold, and it is immaterial on which they are constructed, and any otherkind of air passage or flue communicating from the open interior of themold to the inclosed annular chamber L between the mold and the flask Aand then out to the open air would be a substitute for the device shown.In the construction shown the air passes out from the flask through theannular space i. (Sh own in Fig. 1.) The ribs'h h do not appear in themold shown in Fig. 6, because the internal flange of flask A and theannular ring or plate D are dispensed with. The interior annular cornersof the mold are beveled, as seen at a c, Fig. 4. The offiee of theseannular bevels is to hold the casting concentrically in the mold whileit is cooling and shrinking, and also to prevent the shrinkage fromleaving the casting loose in the mold. In this case the efiect ofshrinkage is to cause the casting to contract and draw down upon and hugthe bevels a c.

The designs A, A", A, Af, and A are five modifications of practically.the same flask. Each consists of an annulus, within which the mold iseither permanently or removably, but concentrically, fixed, but differssomewhat as to the means for holding the mold, as will hereinafterappear.

The flask shown in Fig. 1 consists of an annular shell A of L shape incross-section, the central portion of the head or disk being removed tocoincide with the internal diameter of the mold. This part of the flaskis provided with an annular cover-plate D, the external diameter ofwhich is something less than the internal diameter of the flask, thusleaving an annular space it between the edge of the cover and the flask.A series of links G G are fitted to the head of the flask, as at H II,and extend through. the same between the edge of the mold and theinsideof the wall of the flask and are so arranged that when the mold isplaced in position in the flask its periphery will bear against theselinks G G, so as to incline their outer or free ends out against theinner surface of the flask, as shown in Fig. 1. By these means the moldis centrally adjusted in the flask. The cover D being laid over the moldinside of the links, the keys J J are then passed through the links andrest on the cover and on the edge of the rim of the flask, and, beingtightly driven home, securely bind together the mold and the severalparts of the flask. hen the mold and links G G are in position as seenin Fig. 1, the round edge of the mold is tangent to each link and bearsagainst it. When the mold is charged and expands with the heat, theselinks spring or yield slightly to accommodate themselves to suchexpansion, and

when the parts are cool they return to their proper shape again. Theexterior of the flask has a raised rib 0" extending around itscircumference, which is provided to co-operate with the groove orgrooves in the guiding or driving rolls to prevent the flask from displacement sidewise when in motion.

The means provided for rotating the flask consists of a series ofdrivingrolls B B, mounted on shafts G O, which rotate in journal-boxes SS. These journal-boxes are made adjustable with reference to each otherby means of a screw Y, provided with right and left threads f g, whichwork in nuts in the blocks S S. The boxes S S slide on ways 76. Theextensible adjustment secured by the screw Y is necessary to accommodateflasks of different diameters in cases where two supporting and drivingrolls to each flask are used, as in Figs. 1 and 2. The shafts O O areeach provided with a driving-pulley V V and are driven from a motor bythe belt WV, which passes around both of them, as seen in Fig. 2. Asmany driving-rolls B B may be arranged in a gang on one shaft as can beprofitably operated.

Each of the molds is provided with a runner for conveying the moltenmetal from the ladle to the mold. This consists of funnel M, having aclamping attachment N for fastening the same to a bar 0, and a tubularspout U, terminating in a curved nozzle N, for delivering the metal tothe mold. This clamping attachment, as shown, is merely an enlargementon the casting of the funnel M, which is bored out to take in the bar 0,and the part which is to form the ears is sawed through parallel withthe axis of the bore and then fitted with the clamping-screw, wherebythe ears N of the clamp may be pinched together upon the bar 0. Thisclamping device may be of any other form of construction. This curve Npoints in the direction of the rotation of the mold and is soconstructed that it may deliver the metal to the revolving mold at avelocity corresponding with or approximating as nearly as may be to theve locity of the rotation of the mold, so that the metal shall bedeposited in the mold with as little agitation as possible and in awaythat its tendency to flow in the mold will be obviated.

The gang of molds is provided with a corresponding gaug of runners,which are arranged on the bar 0 in substantially the manner shown, eachrunner being attached by a clamp N and set-screw b. By means of thisclamp the runner can be turned and adjusted on the bar 0 to any desiredinclination or may he slid along the bar for lateral adjustment. The bar0 extends over the whole gang of molds and is supported at each end inthe forks e e of the vertically-adjustable supports P P. These supportsmay be constructed in any suitable way to secure vertical adj ustment,and in this case I have shown them as consisting of a stationary screwP, which works friction-rollR R is pivoted.

in the rotary nut Q. This nut is seated in a suitable bearing (see Fig.5) provided therefor in the top of standard R. The bar 0 when inposition is secured to the tops of its adjustable supports P P by meansof set-screw 61. After the pouring of a set of tires the setscrews d areloosened and the bar 0, with its appendages, may be picked up by a craneor otherwise and swung around out of the way.

In connection with the apparatus hereinbefore described I employ one ormore crucibles or ladies to handle the metal, partial views of which areseen in Figs. 1 and 2. These are very similar in design to those used insteelfoundries and are each provided with a discharge spout or nozzle17. at the bottom, which is closed by a stopper m, which is attached toa handle and is made of the usual refractory material. These ladles aremounted on trucks running on tracks above the runners (not shown in thedrawings) and are so constructed by placing the spouts to one side ofthe ladle that two of them can be brought into position over arunner-funnel, and their contents may be either successively orsimultaneously discharged into the runner.

By means of this apparatus it becomes feasible to make compound castingsof two or more different metals. By filling one ladle with steel and theother one with iron a compound casting may be made by partially fillingthe mold from one ladle and then cutting off this supply, introducingthe other metal to complete the casting. In doing this care is taken notto allow the runner to become empty of one metal before the other isintroduced, and thus a perfect union of the two metals in the casting issecured.

In cases where protection would be necessary or desirable I haveprovided a shield S, Figs. 6 and 8, for each of the molds, which issecured to the bar 0 by the yoke or clamp N '0. This guards againstaccidents resulting from matter thrown from the mold or flask bycentrifugal force. These shields are removed with the bar 0 and therunners whenever the same are displaced for the purpose of emptying theflasks.

I have shown in Figs. 7 and 8 two methods of guiding the flask topreserve its proper working position in connection with the supportingor driving roll or rolls. These are substitutes for the rib rand groovess of Fig. 1. In Fig. 7 I have shown two opposite guides or studs P P,one of which is seen in Fig. 8. When these are employed, they can beused in such numbers and at such points on either side of the flask asexperience may dictate. Another device is also shown in Fig. 7, whichconsists of two fixed studs arranged one on each side of the flask, uponeach of which a These run in driving-rolls.

driving-roll, upon which the flask rests, and two guiding-rolls B B,placed fore and aft the driver. In this modification of my apparatus thesurfaces of the flask and of all the rolls are smooth, the flask beingkept in position by the stud-guides P.

The modification of flask seen in Fig. 7 differs from that of Fig.1 inhaving two similar annular loose heads or covers in place of one looseand one solid cover and in the further particular that the flask moldand covers are held together exclusively by links and keys.

In order to assemble the several parts concentrically, the severalblocks WV (shown in detail in Fig. 9) are inserted between the peripheryof the mold and the inner edge of the flask. The links G, being thinner,are readily pushed through the annular space between the mold and flaskand are held in position by means of keys or wedges J J, insertedthrough their protruding ends, as shown. These keys bear against thesurface of the covers D and the edge of the flask A, and, being tightlydriven up, securely bind the whole combination together.

In the modification shown in Fig. 6 the flask consists simply of a ringor hoop of the same thickness as the thickness of the mold provided withthe circular rib r, as in Fig. 1, but having no side covers, as in Figs.1, 2, and 7. The flask and mold are held together by links and keyssimilar to those shown in Fig. 7. For greater convenience in setting upa flask and mold one set of keys is preferably made like J in Fig. 6,having a shoulder which sets up close to the link and aids in preventingdisplacement. The other key is inserted through the other end of thelink and rests on the mold and edge of the flask. In this variety I haveshown the interior of the flask-rim heavily chambered, as at L, which isdone for the purpose of making the flask tighter and of creating acooling-chamher around the wheel-mold.

Fig. 11 shows a style of combined flask and mold. The mold consists ofthe two sections E and F, parting at the joint at 00. Section E issurrounded by the rims A R, with which it is connected by the spokes orwebs a and I). These webs are of such thickness that they can yieldunder the expansion by heat of the interior mold, and by reason of theirdiagonal position will do so Whenever the mold and rim are unequallyheated. Thus these webs constitute a yielding connection between themold and external rims and hold the mold in a central position, as wellas yield to its calorific expansion in the casting process.

Figs. 12 and 13 show the edge view of the webs. The two halves of themold are held together by means of links G and keys J, the links passingaround webs b and projecting above the surface of the mold sufficientlyto admit of the insertion of key J, as shown in Fig. 11.

In'Fig. 14. the provisions for centering the mold consist of a series ofcurved flat springs S which are inserted at intervals between the flaskand the mold, so that the edge of the mold shall bear against the highpart of the spring.

For convenience in setting up the mold and as a means of bringing thesprings S to a uniform adjustment an annular shoulder or groove 0 is cutin the interior of the annulus A within which one end of said springsfind lodgment, the other end being free to come and go with theexpansion of the mold.

My method of making tires or other similar cylindrical castings withthis apparatus consists in first properly setting up each flask and moldand mounting it in its proper position on its driving-rollers. The moldthen is preferably heated and smoked slightly, the mold meanwhilerevolving slowly. This done, the molds are then speeded up to a speed offrom three to six hundred revolutions per minute, or at a ratesufficiently rapid that the centrifugal force exerted on the metal inthe molds will firmly and soundly condense it, so that all blow-holesand like imperfections will be obliterated. The metal is then rapidlypoured into the funnel M of the runner, and as the mold revolves it israpidly delivered through the nozzle N as nearly as may be at a tangentto the circle of revolution of the mold. In this way the metal isdelivered in the mold in fused spiral layers, whereby the casting isrendered nearly, if not entirely, homogeneous.

I therefore claim as my invention- 1. The combination of the annularflask inclosing annular cover-plates and inclosed annular mold, withspace between said mold and flask, and yielding links and keys foruniting said side plate, mold, and flask and binding the parts of thecombination together, substantially as specified.

2. The combination,with theIrevolving a11- nular flask and inclosedmold, of a tubular runner having a funnel-shaped top attached to aremovable bar supported by suitable standards, substantially asspecified.

3. The combination, with a gang of revolving molds, of a correspondinggang of runners, each being attached by an adjustingclamp to a commonmoveable bar, and standards for supporting the same, said bar beingremovable from said standards, substantially as set forth.

4. The described annular flask, having circumferential guiding groove orrib and carrying a concentric annular mold, in combination with a singlepair of supporting-rollers, each ribbed or grooved to co-operate withthe corresponding devices on the flask, by the revolution of one or bothof which the flask is rotated independently of the other drivingconnections, substantially as described, and for the purposes set forth.

5. The combination, with a rotating annumounted on a correspondingseries of supporting and driving rolls, substantially in the mannerdescribed, and for the purposes set forth.

In testimony whereof I have hereto subscribed my name this 24th. day ofJanuary, A. D. 1887.

WVILLIAM O. FARNUM.

In presence of- FRANKLIN SCOTT, O. ERNEST OANFIELD.

